Concrete impregnating

Sulfur can replace 30-50% of the asphalt in the hlends used for road construction. Road surfaces made from asphalt-sulfur hlends have nearly double the strength of conventional pavement, and it has been claimed that such roads are more resistant to climatic conditions. The impregnation of concrete with molten sulfur is another potential large sulfur use. Concretes impregnated with sulfur have better tensile strength and corrosion resistance than conventional concretes. Sulfur is also used to produce phosphorous pentasulfide, a precursor for zinc dithiophosphates used as corrosion inhibitors. 

Use Paints, rubber plasticizers, curing concrete, impregnating paper, adhesives, hot-melt coatings, pressure-sensitive tapes. 

The technology of concrete impregnation with organic polymers is the most commonly known [173]. The sulphur impregnated concrete was also studied, however, the durability of this material was poor, because of the instability of sulphur in the highly basic cement matrix. 

There are many questions to resolve as the technology of concrete impregnation is concerned. They relate mainly to the durability of polymers in the basic environment of concrete and the formation of stresses [171]. 

Uses Ureth for high gloss coatings, floor sealers, wood coatings, concrete impregnation for interior use crosslinking agent with alkyd resins for two-component sterns... 

Specimen no. Specimen length from the column top (cm) Concrete impregnation with the surfactant Compressive strength of concrete (MPa)... 

Figure 11.11. Compressive stress-strain curves for concrete impregnated with poly(methyl methacrylate). Polymer loading MMAl > MMA2 > MM A3. Specimen L25 is a latex-modified concrete. (Dahl-Jorgensen and Chen, 1973.)...

Figure 11.12. Compressive stress-strain curves for concrete impregnated with various combinations of methyl methacrylate (MMA), n-butyl acrylate (BA), and a crosslinking agent, trimethylolpropane trimethacrylate (TMPTMA). Specimen BI, 90 MMA/10 TMPTMA ...

Bis [[[4-(ethenyloxy) methyl] cyclohexyl] methyl] terephthalate 1,4-Cyclohexanedicarboxylic acid Dicyclopentenyl acrylate Dicyclopentenyl methacrylate Dimethyl maleate 2-Hydroxyethylethylene urea Hydroxypropyl methacrylate Jsooctyl acrylate 2-Phenoxyethyl methacrylate 3-[(Prop-1-en-2-yl) phenyl] prop-2-yl isocyanate N-Vinyl formamide monomer, concrete impregnation Methyl methacrylate monomer, concrete resurfacing Dicyclopentenyl methacrylate monomer, conductive polymers... 

Figure 10.17 Tensile stress-strain curves for concrete impregnated with various compositions of MMA, BA and TMPTMA (cT Table 10.1), after Dahl-Jorgensen et al. (1974).

Z. Jamrozyand J. Sliwinski, Properties of steel fibre reinforced concrete impregnated with methyl methacrylate , Int. J. Cem. Comp. 1,1979,117-124. 

There are less exotic ways of increasing the strength of cement and concrete. One is to impregnate it with a polymer, which fills the pores and increases the fracture toughness a little. Another is by fibre reinforcement (Chapter 25). Steel-reinforced concrete is a sort of fibre-reinforced composite the reinforcement carries tensile loads and, if prestressed, keeps the concrete in compression. Cement can be reinforced with fine steel wire, or with glass fibres. But these refinements, though simple, greatly increase the cost and mean that they are only viable in special applications. Plain Portland cement is probably the world s cheapest and most successful material. 

Sadegzadeh, M. and Kettle, R. J., Abrasion resistance of polymer impregnated concrete. Concrete, 32-34, May (1987). 

Uses Manufacturing methacrylate resins and plastics (e.g., Plexiglas and Lucite) impregnation of concrete. 

Sulfur Impregnation (14). Stronger and more durable products such as Portland cement concrete, ceramic tile and even wood and paper products have been shown to be feasible. In addition, sulfur as an impregnant for fabric liner systems would have application in ponds, holding tanks, etc. 

Ethyl silicate (tetraethoxysilane) is often used without modification as a water-repellent material for concrete and masonry in general. All, or nearly all. the ethoxyl groups are hydrolyzed by the moisture of the air to form cross-linked watcr-rcpcllcnt polymers. The material is applied in desirable thickness, dissolved in some volatile solvent which soon evaporates. Silicone resins which arc partially condensed before application, or even fully condensed, can also be used here. In the latter case, hardness is achieved on evaporation of the solvent. Certain silicone resins arc useful as hydrophobic agents for the impregnation of paper and fabrics. 

Impregnated wood, glass-reinforced polyester or precast concrete are acceptable materials for water basin. 

Evacuation, Soaking, and Pressurizing. The impregnation of concrete with monomer is essentially a displacement of the air in the void... 

For processing purposes the monomer should have a relatively high boiling point or low vapor pressure under polymerization conditions to limit vaporization losses between the time the concrete specimen is impregnated and the time it is polymerized fully. 

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